30 mm
Its a 28mm socket.
I changed my oil today, the drain plug is 15 mm.
It is 17mm.
It is 25 mm socket.
If it's the "oil" drain plug, the size wrench is, better yet use a socket wrench=13mm.
17mm
If the drain plug is original equipment, it takes a 17mm wrench or socket.
it takes 1" socket on it good luck on it
5/8
It's in metric: 14mm.
30mm or 1-3/16"
There is a good chance that it takes a standard size socket rather than a metric socket, it was like this on my Toyota Celica. 17mm